A WebmasterWorld thread has tips from senior member wheel on how to get links from .edu pages, even when they might not be .edu pages.
Wheel said that many professors have web sites that might not be on an edu top level domain. Since edu links might not be better than any other TLD, then why not go after any link from any professor's site?
Searching on things like widget instructors, widget courses, and anything you can think of related to education in your niche is likely to provide a rich list of potential link sources.
The same goes with college or university students. Find their web pages and send them some beer. Of course, as discussed in the thread, that might be considered a paid link. ;-)
Forum discussion at WebmasterWorld.